checkbox and textbox checking....

hi there I have a form that has a field object that has many checkboxes. There'e this one checkbox which says others. How do i able and disable the textbox based on whether that checkbox has been checked using javasacript??

hi there i managed to solve it

function toggleOther ()
{
if (document.getElementById('1').checked == true)
document.getElementById('2').disabled = false;
else
document.getElementById('2').disabled = true;
}

but i got a question... how do i ensure that when the checkbox is ticked the textbox has to have data in it?